AmBev, the Latin American brewer that is now part of the world's largest brewer InBev, has launched an advertising campaign in Peru that claims that Peruvian brewer Union de Cervecerias Peruanas Backus & Johnston SAA (Backus), is selling the most expensive beer in South America.

Ambev and Backus have been at loggerheads since it emerged that Ambev was building a brewery in Peru with plans to sell beer there, a country where Backus has a monopoly at present.

Backus has hit back at the adverts and filed a complaint with consumer defence agency Indecopi, alleging that Ambev Peru's arguments were false and demanding that it pull the advertising campaign.

However Ambev is standing by its claims and a spokesperson for the company yesterday said: "The studies we have carried out show that the beer that is sold in Peru is the most expensive in South America."